Polio is a serious disease that cripples the life of the affected person. It is caused by a virus that enters the body through fecal-oral route. This article will summarize the key information related to polio and help you learn more about this dangerous disease.
What is Poliomyelitis?
Polio is a highly infectious viral disease. It is one of the world’s most dangerous diseases affecting children. The virus attacks the central nervous system and children within the age group of under 5 years are most vulnerable. Polio leads to permanent paralysis. It can spread person to person through the fecal-oral route.
The term poliomyelitis means gray (polios) and marrow (myelos) derived from Ancient Greek. The suffix ‘itis’ means inflammation. In other words, it is an inflammation of the gray matter of the spinal cord. When the infection becomes severe, it can spread to the brainstem and lead to polioencephalitis. This causes the affected person to suffer from apnea. They will require the help of a mechanical ventilator to breathe and survive.
Polio has no cure. The only way to prevent polio is vaccination. United States has eradicated polio from the country by 1979. This is only because of the vaccination efforts undertaken. However, many countries across the world still suffer from polio and is a still fighting for a victory over polio.
What Causes Polio?
Polio is caused by a virus that is transmitted person-to-person. It is passed in areas where water from the toilets contaminates the drinking water. It can also spread through contaminated food. The virus is so contagious that people around an infected person can become infected with it through contact.
Types of Polio
There are three types of poliomyelitis depending on the symptoms. It can either be symptomatic (95% cases) or asymptomatic (5% cases). These conditions appear in the following forms:
Sub-clinical or Abortive Polio
Around 95% of the cases are sub-clinical type. The affected person suffers from no symptoms as the virus does not attack the brain and central nervous system. It only leads to flu-like symptoms such as upper-respiratory tract infection, fever, diarrhea, sore throat, etc.
This is a severe form of polio where the symptoms are associated with aspectic meningitis called nonparalytic polio. Symptoms include sensitivity to light, stiff neck.
This is the most severe and debilitating form of polio. It causes permanent muscular paralysis and may even lead to death.
One can recover from the sub-clinical and nonparalytic polio. However, paralytic polio is the most severe form of all. It can affect the nerves of the limbs and lungs.
Symptoms of Polio
The symptoms of polio according to the three types are as follows:
The symptoms last for about three days like:
- Sore throat
The symptoms last for about a few days to a couple of weeks like:
- Sore throat
- Problems swallowing
- Breathing difficulty
- Neck stiffness, inability to bend the neck forward
- Back stiffness
- Pain and stiffness of the arms and legs
- Tender muscles
- Muscle spasms
When one is affected with paralytic polio, they will first show signs of nonparalytic polio. Later they develop symptoms such as:
- Severe muscle spasms
- Severe muscle pain
- Floppiness of limbs usually on one side of the body
- Temporary or permanent sudden paralysis
- Deformed lips
In some, the polio virus may affect the respiratory muscles that leads to permanent paralysis causing death.
After one recovers from polio, they may suffer from post-polio syndrome. This causes symptoms that appear anytime, even 35 years after recovering from polio. These include:
- Muscle atrophy
- Easily becoming tired or fatigued
- Problems breathing
- Joint weakness
- Sleep apnea
- Weakness in muscles that were unaffected by polio
Diagnosis of Polio
Paralytic polio is diagnosed when an affected limb shows signs of flaccid paralysis in one or more limbs. The patient shows decrease or absence of tendon reflexes of the affected limbs. Lab tests such as a sample of stool or a swab from the pharynx will help detect polio. The CSF fluid collected shows increase in white blood cells with elevated level of protein. Once poliovirus is detected, it is sent for genetic mapping. This helps determine if the virus is wild type or vaccine type. This will help understand the number of contagious asymptomatic carriers for the wild type polio virus in the wild.
Treatment for Polio
There is NO cure for polio. It can only be prevented. But once a person is affected, the only treatment offered is to get relief from the symptoms. The polio management options include:
- Painkillers are prescribed to help get relief from muscle pain, spasms and headaches
- Urinary tract infections can be treated with antibiotics
- Use of portable ventilators to help assist in breathing
- Physical therapy to treat pain of the muscles affected by polio
- Corrective braces to assist the person with walking
- Use of wheelchair in cases severe leg weakness
- Physical therapy to help cure the pulmonary problems and increase the endurance factor of the lungs to improve breathing
Prognosis for patients who suffer from abortive polio is good. These patients recover fully and suffer from no problems. Those with aseptic meningitis to recover within 10 days. However, patients with spinal polio suffer from permanent paralysis. Half of the patients with spinal polio whose nerve cells are not destroyed recover fully. One-quarter of the remaining patients suffer from mild disability and the remaining quarter are severely disabled. Patients with respiratory polio die due to paralysis of the respiratory muscles.
Prevention of Polio
The only way to treat polio is prevent it from infecting children. Vaccination is the only way to prevent polio. There are two types of polio vaccines. They include the attenuated virus vaccine and inactivated poliovirus vaccine or Salk vaccine. Another vaccine called oral polio vaccine (OPV) was subsequently developed. It was produced by repeated passage of the virus through nonhuman cells maintained at sub physiological temperatures. A single dose of this vaccine helps produce immunity to all three poliovirus stereotypes in 50% of the recipients. Three doses of oral polio vaccine are enough to produce immunity against all three stereotypes in 95% recipients. Today, it is the only vaccine to be used worldwide. OPV is easy to administer and helps build strong immunity in the intestine against poliovirus. However, on very very rare occasions, the attenuated virus in OPV can revert back to its original form and lead to paralysis.
This was all about poliomyelitis. Polio is a debilitating condition and can cripple the life of an individual immensely. Vaccination is the only way to prevent and eradicate polio. Follow the government lain guidelines for polio vaccination and help the children of today as well as future live a polio free life.
Written by: Saptakee sengupta
Date last updated: April 01, 2015